em has to dial some phone number before you can get on the net. Unlike other ISP accounts (direct cables which keep you online for 24 hours a day), you get a dynamic IP address(9) (and not a static one like on direct cable connections) since you have to connect and disconnect instead of just staying online all the time. Every time you re-connect you are assigned with a different IP address.32. Packet - a piece of data that travels over a network (such as the Internet or local/wide area networks). A packet consists of two main parts: the header and the data itself. The header contains all sorts of nifty values such as the TTL (Time To Live) and more (you can read about those in the Modem Speedup section at http://blacksun.box.sk). The data part contains the actual data that the packet is carrying.On a regular dial-up account(31), the size of a packet should be 576 bytes (including the header), but on direct cable connections a packet would be much bigger (again, see Modem Speedup section at blacksun.box.sk).33. Unix password files - Every Unix system has a password file. They contain a list of users, their passwords and some important information about them. The password file is located at /etc/passwd. Each line represents a user.Each line consists of 7 fields, seperated by : marks (commas).A line in a password file should look like this:Username:encrypted password:UID:GID:short description:home directory:shellUsername - the user's username.Encrypted password - the user's password (encrypted for higher security). An encrypted password is always 13 characters long.UID - User ID. Each user has an ID number. If your UID is 0 it means you have root access(14).GID - Group ID. You can set groups (for example: all the workers in the accounting division) and set special permissions to that entire group. Root has GID 0.Short description - short description in human language.Home directory - the directory where all of the user's personal configura...
